A staff member tests samples of the COVID-19 inactivated vaccine at a vaccine production plant of China National Pharmaceutical Group (Sinopharm) in Beijing, capital of China, April 11, 2020. (Xinhua/Zhang Yuwei)

The open-label trial in 108 healthy adults demonstrates promising results after 28 days and the final results will be evaluated in six months, The Lancet said in a press statement.

LONDON, May 22 (Xinhua) -- China's COVID-19 vaccine trial, the first such vaccine to reach phase 1 clinical trial, has been found to be safe, well-tolerated, and able to generate an immune response against SARS-COV-2 in humans, according to a study published online on Friday by medical journal The Lancet.

The open-label trial in 108 healthy adults demonstrates promising results after 28 days and the final results will be evaluated in six months, The Lancet said in a press statement. Further trials are needed to tell whether the immune response it elicits effectively protects against SARS-COV-2 infection, said the medical journal.

A staff member tests samples of the COVID-19 inactivated vaccine at a vaccine production plant of China National Pharmaceutical Group (Sinopharm) in Beijing, capital of China, April 11, 2020. (Xinhua/Zhang Yuwei)

"These results represent an important milestone. The trial demonstrates that a single dose of the new adenovirus type 5 vectored COVID-19 (Ad5-nCoV) vaccine produces virus-specific antibodies and T cells in 14 days, making it a potential candidate for further investigation," said Professor Wei Chen from the Beijing Institute of Biotechnology in Beijing, China, who is responsible for the study.

"However, these results should be interpreted cautiously. The challenges in the development of a COVID-19 vaccine are unprecedented, and the ability to trigger these immune responses does not necessarily indicate that the vaccine will protect humans from COVID-19. This result shows a promising vision for the development of COVID-19 vaccines, but we are still a long way from this vaccine being available to all," said Chen. ■